Supplements and Nortriptyline.
Nortriptyline, sold under the brand name Allegron, is an antidepressant: depending on the agent, it acts on serotonin, noradrenaline, or both.
Nortriptyline sits in the BNF "other antidepressants" group. The group includes the SNRIs (venlafaxine, duloxetine), the atypicals (mirtazapine, agomelatine, vortioxetine), and the older tetracyclics. The clinical class matters more than the BNF group, because the supplement profile differs sharply across it. SNRIs share the SSRI serotonergic concerns. Mirtazapine sits closer to the sedating, appetite-stimulating profile. Agomelatine is heavily liver-metabolised with mandatory LFT monitoring. Where these antidepressants share a supplement surface, it is St John's Wort (hard exclude across the class), 5-HTP (hard exclude on serotonergic grounds), and any supplement with significant sedating or activating effect depending on the agent. Discontinuation profiles differ too. Venlafaxine has the heaviest withdrawal syndrome of common antidepressants. Agomelatine probably the lightest.
Below are the 5 documented pairs we have explicitly assessed against Nortriptyline in the Distil database: 5 amber. The pairs cluster around 3 mechanisms: Cholinergic vs anticholinergic (opposing), CYP induction, and Additive serotonergic activity. Every call is cited to either a clinical reference (PMID) or the British National Formulary. Anything not on this list is either still to be assessed or beyond our database scope. The checker beneath surfaces assessments by supplement, and the missing-item form at the bottom of the page routes any uncatalogued supplement into our next curation pass.
Documented interactions
Cholinergic vs anticholinergic (opposing)
Huperzine A raises acetylcholine, while nortriptyline has an anticholinergic effect that blocks it. The two can work against each other, and nortriptyline may blunt any benefit from huperzine A. It is worth mentioning the huperzine A to your prescriber.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
CYP induction
St John's Wort can speed up how the body clears nortriptyline, lowering its level in your blood so it works less well for low mood or pain. In a study, blood levels of nortriptyline dropped by about 40 percent. If you take nortriptyline, mention St John's Wort to your GP or pharmacist rather than starting it on your own, and watch for symptoms returning.
Additive serotonergic activity
5-HTP raises serotonin, while nortriptyline works mainly on noradrenaline and has only weak serotonin activity. Any added serotonin effect is likely to be small, but it is worth mentioning the 5-HTP to your GP and watching for restlessness, sweating, or muscle twitching, especially if your dose has recently changed.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Tryptophan is the building block your body uses to make serotonin, while nortriptyline works mainly on noradrenaline and has only weak serotonin activity. Any added serotonin effect is likely to be small, but it is worth mentioning the tryptophan to your GP and watching for restlessness, sweating, or shivering if your dose has recently changed.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Saffron has its own mild antidepressant effect that appears to act on serotonin, and nortriptyline acts on serotonin and noradrenaline too. Taking them together may add up. Most people tolerate it, but discuss it with your GP before stacking, especially if your dose has recently changed.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
What this list does not say. Pairs not flagged here are not implicitly safe. They are either not yet in our database, or fall outside our inclusion scope (food-supplement interactions only; for drug-drug interactions, the BNF is authoritative). Use the checker below to surface any supplement, and submit a missing item if you take something we have not catalogued.
How we grade severity, choose what's in scope, and what we exclude.
Every call on this page is reasoned. We publish the full rubric for severity tiers, the medication inclusion logic, the evidence grades we accept, and what we deliberately leave out. About three thousand words. Worth reading once if you use this tool more than occasionally.
Read the full methodologyWant this checked across everything you take?
This page checks the pairs you enter. The personalised Distil report goes further:
- the same graded, cited interaction check across your whole stack, not just the pairs you thought to type in
- where your current routine may be leaving you short of your goals
- the evidence-backed compounds worth adding, and the ones worth dropping
It's a paid report: £79, or £49 for the first 25 customers. The interactions check is one section of it, and you can read a real one in full before you buy.
See a real sample reportSomething missing?
If a supplement or medication you take isn't in our autocomplete, tell us. We go through what people flag every week and add what's missing.